Encapsulated display devices

ABSTRACT

An encapsulated display device. The device includes a substrate, an environmentally sensitive display device adjacent to the substrate, and at least one first barrier stack adjacent to the environmentally sensitive display device. The barrier stack encapsulates the environmentally sensitive display device. It includes at least one first barrier layer and at least one first polymer layer. The encapsulated display device optionally includes at least one second barrier stack located between the substrate and the environmentally sensitive display device. The second barrier stack includes at least one second barrier layer and at least one second polymer layer. A method for making an encapsulated display device is also disclosed.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of U.S. application Ser. No.09/427,138, filed Oct. 25, 1999 now U.S. Pat. No. 6,522,067 entitled“Environmental Barrier Material for Organic Light Emitting Device andMethod of Making.”

BACKGROUND OF THE INVENTION

The present invention relates generally to display devices, and moreparticularly to environmentally sensitive display devices encapsulatedin barrier stacks to prevent degradation.

There is a need for versatile visual display devices for electronicproducts of many different types. Many different display devices arepresently being used, including liquid crystal displays (LCDs), lightemitting diodes (LEDs), light emitting polymers (LEPs), electronicsignage using electrophoretic inks, electroluminescent devices (EDs),and phosphorescent devices. Many of these display devices areenvironmentally sensitive. As used herein, the term environmentallysensitive display device means display devices which are subject todegradation caused by permeation of environmental gases or liquids, suchas oxygen and water vapor in the atmosphere or chemicals used in theprocessing of the electronic product.

Although many current displays use glass substrates, there is a trendtoward the use of plastic substrates. Plastic substrates are critical tofuture generations of electronic products and associated technologiesbecause they are light weight, impact resistant, and cost effective.However, the gas and liquid permeation resistance of plastics is poor,often several orders of magnitude below what is required for sustaineddevice performance. Barrier coatings are applied to substrates todecrease their gas and liquid permeability. Barrier coatings typicallyconsist of single layer thin film inorganic materials, such as Al, SiO₂,Al₂O₃, and Si₃N₄ vacuum deposited on polymeric substrates. The bestsingle layer coatings reduce oxygen and water vapor permeability tolevels of about 0.1 to 1.0 cc/m²/day and about 0.1 to 1.0 g/m²/day,respectively. (Conditions were not reported. The testing is believed tobe at 23° C.) However, many displays require oxygen permeability levelsof between about 10⁻⁶ and 10⁻⁵ cc/m²/day, and water vapor permeabilitylevels between about 10⁻⁴ and 10⁻² g/m²/day. The environmentalsensitivity of the display devices limits the lifetime, reliability, andperformance of devices constructed on plastics, which has retarded thedevelopment of display devices made with plastic substrates.

Thus, there is a need for an improved, lightweight, barrier constructionwhich can be used to encapsulate environmentally sensitive displaydevices and prevent the deterioration caused by gas and liquidpermeation, and for methods for making such encapsulated environmentallysensitive display devices.

SUMMARY OF THE INVENTION

The present invention meets these need by providing an encapsulateddisplay device and a method for making such a device. The deviceincludes a substrate, an environmentally sensitive display deviceadjacent to the substrate, and at least one first barrier stack adjacentto the environmentally sensitive display device. By adjacent, we meannext to, but not necessarily directly next to. There can be additionallayers intervening between the adjacent layers. The barrier stackencapsulates the environmentally sensitive display device. It includesat least one first barrier layer and at least one first polymer layer.The encapsulated display device optionally includes at least one secondbarrier stack located between the substrate and the environmentallysensitive display device. The second barrier stack includes at least onesecond barrier layer and at least one second polymer layer.

Preferably, either one or both of the first and second barrier layers ofthe first and second barrier stacks is substantially transparent. Atleast one of the first barrier layers preferably comprises a materialselected from metal oxides, metal nitrides, metal carbides, metaloxynitrides, metal oxyborides, and combinations thereof.

Either one of the first and second barrier layers can be substantiallyopaque, if desired. The opaque barrier layers are preferably selectedfrom opaque metals, opaque polymers, opaque ceramics, and opaquecermets.

The substrate can either be flexible or rigid. It is preferably made ofa flexible substrate material, such as polymers, metals, paper, fabric,and combinations thereof. If a rigid substrate is used, it is preferablya ceramic (including glass), a metal, or a semiconductor.

The polymer layers of the first and second barrier stacks are preferablyacrylate-containing polymers. As used herein, the termacrylate-containing polymers includes acrylate-containing polymers,methacrylate-containing polymers, and combinations thereof. The polymerlayers in the first and/or the second barrier stacks can be the same ordifferent.

The environmentally sensitive display device is preferably selected fromliquid crystal displays, displays using electrophoretic inks, lightemitting diodes, electroluminescent devices, and phosphorescent devices.

The encapsulated display device can include additional layers ifdesired, such as polymer smoothing layers, scratch resistant layers, orother functional layers. The encapsulated display device can alsoinclude a lid adjacent to the at least one first barrier stack.

The present invention also involves a method of making the encapsulateddisplay device. The method includes providing a substrate having anenvironmentally sensitive display device thereon, and placing at leastone first barrier stack over the environmentally sensitive displaydevice to encapsulate the environmentally sensitive display device. Thebarrier stack includes at least one first barrier layer and at least onefirst polymer layer.

The environmentally sensitive display device can be placed on thesubstrate by deposition or by lamination. The at least one first barrierstack can be placed over the environmentally sensitive display device bydeposition, preferably vacuum deposition, or by laminating the barrierstack over the environmentally sensitive device. The lamination can beperformed using an adhesive, solder, ultra sonic welding, pressure, orheat.

A second barrier stack can be placed on the substrate before theenvironmentally sensitive display device is placed there. The secondbarrier stack includes at least one second barrier layer and at leastone second polymer layer. The second barrier stack can be deposited onthe substrate, preferably by vacuum deposition.

The substrate can be removed from the encapsulated environmentallysensitive display device, if desired.

Accordingly, it is an object of the present invention to provide anencapsulated display device, and to provide a method of making such asdevice.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-section of one embodiment of the encapsulated displaydevice of the present invention.

FIG. 2 is a cross-section of an alternate embodiment of the encapsulateddisplay device of the present invention.

DESCRIPTION OF THE INVENTION

One embodiment of the encapsulated display device of the presentinvention is shown in FIG. 1. The encapsulated display device 100includes a substrate 105, an environmentally sensitive display device110, and a first barrier stack 115. The first barrier stack 115 includesa barrier layer 120 and a polymer layer 125. The first barrier stack 115encapsulates the environmentally sensitive display device 110,preventing environmental oxygen and water vapor from degrading theenvironmentally sensitive display device.

The substrate 105 can be either rigid or flexible. A flexible substratecan be any flexible material, including, but not limited to: polymers,for example polyethylene terephthalate (PET), polyethylene naphthalate(PEN), or high temperature polymers such as polyether sulfone (PES),polyimides, or Transphan™ (a high glass transition temperature cyclicolefin polymer available from Lofo High Tech Film, GMBH of Weil amRhein, Germany); metal; paper; fabric; and combinations thereof. Rigidsubstrates are preferably ceramics, metals, or semicondutors.

The environmentally sensitive display device 110 can be any displaydevice which is environmentally sensitive. Examples of environmentallysensitive display devices include, but are not limited to liquid crystaldisplays (LCDs), light emitting diodes (LEDs), light emitting polymers(LEPs), electronic signage using electrophoretic inks,electroluminescent devices (EDs), and phosphorescent devices. Thesedisplay devices can be made using known techniques, such as thosedescribed in U.S. Pat. Nos. 6,025,899, 5,995,191, 5,994,174, 5,956,112(LCDs); U.S. Pat. Nos. 6,005,692, 5,821,688, 5,747,928 (LEDs); U.S. Pat.Nos. 5,969,711, 5,961,804, 4,026,713 (E Ink); U.S. Pat. Nos. 6,023,373,6,023,124, 6,023,125 (LEPs); and U.S. Pat. Nos. 6,023,073, 6,040,812,6,019,654, 6,018,237, 6,014,119, 6,010,796 (EDs), which are incorporatedherein by reference.

In each barrier stack 115, there can be one or more barrier layers 120and one or more polymer layers 125. The barrier layers and polymerlayers in the barrier stack can be made of the same material or of adifferent material. The barrier layers are typically in the range ofabout 100-400 Å thick, and the polymer layers are typically in the rangeof about 1000-10,000 Å thick.

Although FIG. 1 shows a barrier stack with a single barrier layer and asingle polymer layer, the barrier stacks can have one or more polymerlayers and one or more barrier layers. There could be one polymer layerand one barrier layer, there could be one or more polymer layers on oneside of one or more barrier layers, or there could be one or morepolymer layers on both sides of one or more barrier layers. Theimportant feature is that the barrier stack have at least one polymerlayer and at least one barrier layer.

There can be additional overcoat layers on top of the barrier stack,such as organic or inorganic layers, planarizing layers, transparentconductors, antireflective coatings, or other functional layers, ifdesired.

A second embodiment of the encapsulated display device of the presentinvention is shown in FIG. 2. The encapsulated display device 200 has asubstrate 205. There are scratch resistant layers 210 on either side ofthe substrate 205 to protect it. When a scratch resistant layer isincluded, it is preferred that both sides of the substrate have ascratch resistant layer. This helps to prevent curling of a flexiblesubstrate.

On top of the scratch resistant layer 210, there is a polymer smoothinglayer 220. The polymer smoothing layer decreases surface roughness, andencapsulates surface defects, such as pits, scratches, and digs. Thisproduces a planarized surface which is ideal for deposition ofsubsequent layers. Depending on the desired application, there can beadditional layers deposited on the substrate 205, such as organic orinorganic layers, planarizing layers, electrode layers, antireflectivecoatings, and other functional layers. In this way, the substrate can bespecifically tailored to different applications.

The first barrier stack 230 is above the polymer smoothing layer 220.The first barrier stack 230 includes a first barrier layer 235 and afirst polymer layer 240. The first barrier layer 235 includes barrierlayers 245 and 250. Barrier layers 245 and 250 can be made of the samebarrier material or of different barrier materials.

The environmentally sensitive display device 255 is placed over thefirst barrier stack 230. There is a second barrier stack 260 placed overthe environmentally sensitive display device 255 to encapsulate it. Thesecond barrier stack has a barrier layer 265 and a polymer layer 270,although it can have one or more barrier layers and one or more polymerlayers, as discussed above. The barrier layers and polymer layers in thefirst and second barrier stacks can be the same or they can bedifferent.

Although only one first barrier stack and only one second barrier stackare shown in FIG. 2, the number of barrier stacks is not limited. Thenumber of barrier stacks needed depends on the substrate material usedand the level of permeation resistance needed for the particularapplication. One or two barrier stacks should provide sufficient barrierproperties for some applications. The most stringent applications mayrequire five or more barrier stacks.

There is a lid 280 over the second barrier stack 260. The lid can be canbe rigid or flexible, and it can be made of the same types of materialsas the substrate 205.

The method of making the encapsulated display device will be describedwith reference to the embodiment shown in FIG. 2. Any initial layerswhich are desired, such as scratch resistant layers, planarizing layers,electrically conductive layers, etc., can be coated, deposited, orotherwise placed on the substrate. A polymer smoothing layer ispreferably included to provide a smooth base for the remaining layers.It can be formed by depositing a layer of polymer, for example, anacrylate-containing polymer, onto the substrate or previous layer. Thepolymer layer can be deposited in vacuum or by using atmosphericprocesses such as spin coating and/or spraying. Preferably, anacrylate-containing monomer, oligomer, or resin is deposited and thenpolymerized in situ to form the polymer layer. As used herein, the termacrylate-containing monomer, oligomer, or resin includesacrylate-containing monomers, oligomers, and resins,methacrylate-containing monomers, oligomers, and resins, andcombinations thereof.

The first barrier stack is then placed on the substrate. The first andsecond barrier stacks include at least one barrier layer and at leastone polymer layer. The barrier stacks are preferably made by vacuumdeposition. The barrier layer can be vacuum deposited onto the polymersmoothing layer, substrate, or previous layer. The polymer layer is thendeposited on the barrier layer, preferably by flash evaporatingacrylate-containing monomers, oligomers, or resins, condensing on thebarrier layer, and polymerizing in situ in a vacuum chamber. U.S. Pat.Nos. 5,440,446 and 5,725,909, which are incorporated herein byreference, describe methods of depositing thin film, barrier stacks.

Vacuum deposition includes flash evaporation of acrylate-containingmonomer, oligomer, or resin with in situ polymerization under vacuum,plasma deposition and polymerization of acrylate-containing monomer,oligomer, or resin, as well as vacuum deposition of the barrier layersby sputtering, chemical vapor deposition, plasma enhanced chemical vapordeposition, evaporation, sublimation, electron cyclotronresonance-plasma enhanced vapor deposition (ECR-PECVD), and combinationsthereof.

In order to protect the integrity of the barrier layer, the formation ofdefects and/or microcracks in the deposited layer subsequent todeposition and prior to downstream processing should be avoided. Theencapsulated display device is preferably manufactured so that thebarrier layers are not directly contacted by any equipment, such asrollers in a web coating system, to avoid defects that may be caused byabrasion over a roll or roller. This can be accomplished by designingthe deposition system such that the barrier layers are always covered bypolymer layers prior to contacting or touching any handling equipment.

The environmentally sensitive display device is then placed on the firstbarrier layer. The environmentally sensitive display device can beplaced on the substrate by deposition, such as vacuum deposition.Alternatively it can be placed on the substrate by lamination. Thelamination can use an adhesive, glue, or the like, or heat to seal theenvironmentally sensitive display device to the substrate.

The second barrier stack is then placed over the environmentallysensitive display device to encapsulate it. The second barrier stack canbe placed over the environmentally sensitive display device bydeposition or lamination.

The barrier layers in the first and second barrier stacks may be anybarrier material. The barrier layers in the first and second barrierstacks can be made of the same material or a different material. Inaddition, multiple barrier layers of the same or different barriermaterials can be used in a barrier stack.

When a liquid device, such as a liquid crystal display or anelectrophoretic ink, is used, the barrier layers (and any other layersdesired) are deposited on the substrates. The edges of the substratesare then sealed leaving a space between them, and an opening is left inthe seal. The liquid is introduced into the opening in the seal, and theopening is sealed, producing the device.

The barrier layers can be transparent or opaque, depending on the designand application of the display device. Preferred transparent barriermaterials include, but are not limited to, metal oxides, metal nitrides,metal carbides, metal oxynitrides, metal oxyborides, and combinationsthereof. The metal oxides are preferably selected from silicon oxide,aluminum oxide, titanium oxide, indium oxide, tin oxide, indium tinoxide, tantalum oxide, zirconium oxide, niobium oxide, and combinationsthereof. The metal carbides are preferably boron carbide, tungstencarbide, silicon carbide, and combinations thereof. The metal nitridesare preferably selected from aluminum nitride, silicon nitride, boronnitride, and combinations thereof. The metal oxynitrides are preferablyselected from aluminum oxynitride, silicon oxynitride, boron oxynitride,and combinations thereof. The metal oxyborides are preferably zirconiumoxyboride, titanium oxyboride, and combinations thereof.

For most devices, only one side of the device must be transparent.Therefore, opaque barrier layers can be used in some barrier stacksdepending on the design of the display device. Opaque barrier materialsinclude, but are not limited to, metal, ceramic, polymers, and cermets.Examples of opaque cermets include, but are not limited to, zirconiumnitride, titanium nitride, hafnium nitride, tantalum nitride, niobiumnitride, tungsten disilicide, titanium diboride, and zirconium diboride.

The polymer layers of the first and second barrier stacks are preferablyacrylate-containing monomers, oligomers, or resins. The polymer layersin the first and second barrier stacks can be the same or different. Inaddition, the polymer layers within each barrier stack can be the sameor different.

In a preferred embodiment, the barrier stack includes a polymer layerand two barrier layers. The two barrier layers can be made from the samebarrier material or from different barrier materials. The thickness ofeach barrier layer in this embodiment is about one half the thickness ofthe single barrier layer, or about 50 to 200 Å. There are no limitationson the thickness, however.

When the barrier layers are made of the same material, they can bedeposited either by sequential deposition using two sources or by thesame source using two passes. If two deposition sources are used,deposition conditions can be different for each source, leading todifferences in microstructure and defect dimensions. Any type ofdeposition source can be used. Different types of deposition processes,such as magnetron sputtering and electron beam evaporation, can be usedto deposit the two barrier layers.

The microstructures of the two barrier layers are mismatched as a resultof the differing deposition sources/parameters. The barrier layers caneven have different crystal structure. For example, A₂O₃ can exist indifferent phases (alpha, gamma) with different crystal orientations. Themismatched microstructure can help decouple defects in the adjacentbarrier layers, enhancing the tortuous path for gases and water vaporpermeation.

When the barrier layers are made of different materials, two depositionsources are needed. This can be accomplished by a variety of techniques.For example, if the materials are deposited by sputtering, sputteringtargets of different compositions could be used to obtain thin films ofdifferent compositions. Alternatively, two sputtering targets of thesame composition could be used but with different reactive gases. Twodifferent types of deposition sources could also be used. In thisarrangement, the lattices of the two layers are even more mismatched bythe different microstructures and lattice parameters of the twomaterials.

A single pass, roll-to-roll, vacuum deposition of a three layercombination on a PET substrate, i.e., PET substrate/polymerlayer/barrier layer/polymer layer, can be more than five orders ofmagnitude less permeable to oxygen and water vapor than a single oxidelayer on PET alone. See J. D. Affinito, M. E. Gross, C. A. Coronado, G.L. Graff, E. N. Greenwell, and P. M. Martin, Polymer-Oxide TransparentBarrier Layers Produced Using PML Process, 39^(th) Annual TechnicalConference Proceedings of the Society of Vacuum Coaters, Vacuum WebCoating Session, 1996, pages 392-397; J. D. Affinito, S. Eufinger, M. E.Gross, G. L. Graff, and P. M. Martin, PML/Oxide/PML Barrier LayerPerformance Differences Arising From Use of UV or Electron BeamPolymerization of the PML Layers, Thin Solid Films, Vol. 308, 1997,pages 19-25. This is in spite of the fact that the effect on thepermeation rate of the polymer multilayers (PML) layers alone, withoutthe barrier layer (oxide, metal, nitride, oxynitride) layer, is barelymeasurable. It is believed that the improvement in barrier properties isdue to two factors. First, permeation rates in the roll-to-roll coatedoxide-only layers were found to be conductance limited by defects in theoxide layer that arose during deposition and when the coated substratewas wound up over system idlers/rollers. Asperities (high points) in theunderlying substrate are replicated in the deposited inorganic barrierlayer. These features are subject to mechanical damage during webhandling/take-up, and can lead to the formation of defects in thedeposited film. These defects seriously limit the ultimate barrierperformance of the films. In the single pass, polymer/barrier/polymerprocess, the first acrylic layer planarizes the substrate and providesan ideal surface for subsequent deposition of the inorganic barrier thinfilm. The second polymer layer provides a robust “protective” film thatminimizes damage to the barrier layer and also planarizes the structurefor subsequent barrier layer (or environmentally sensitive displaydevice) deposition. The intermediate polymer layers also decoupledefects that exist in adjacent inorganic barrier layers, thus creating atortuous path for gas diffusion.

The permeability of the barrier stacks used in the present invention isshown in Table 1. The barrier stacks of the present invention onpolymeric substrates, such as PET, have measured oxygen transmissionrate (OTR) and water vapor transmission rate (WVTR) values well belowthe detection limits of current industrial instrumentation used forpermeation measurements (Mocon OxTran 2/20L and Permatran). Table 1shows the OTR and WVTR value (measured according to ASTM F 1927-98 andASTM F 1249-90, respectively) measured at Mocon (Minneapolis, Minn.) forseveral barrier stacks on 7 mil PET along with reported values for othermaterials.

TABLE 1 Oxygen Water Permeation Rate Vapor Permeation (cc/m²/day)(g/m²/day)⁺ Sample 23° C. 38° C. 23° C. 38° C. Native 7 mil PET 7.62 — —— 1-barrier stack <0.005 <0.005* — 0.46⁺ 1-barrier stack with ITO <0.005<0.005* — 0.011⁺ 2-barrier stacks <0.005 <0.005* — <0.005⁺ 2-barrierstacks with ITO <0.005 <0.005* — <0.005⁺ 5-barrier stacks <0.005 <0.005*— <0.005⁺ 5-barrier stacks with ITO <0.005 <0.005* — <0.005⁺ DuPontfilm¹ 0.3 — — — (PET/Si₃N₄ or PEN/Si₃N₄) Polaroid film³ <1.0 — — —PET/Al² 0.6 — 0.17 — PET/silicon oxide² 0.7-1.5 — 0.15-0.9 — Teijin LCDfilm <2 — <5 — (HA grade - TN/STN)³ *38° C., 90% RH, 100% O₂ ⁺38° C.,100% RH ¹P. F. Carcia, 46^(th) International Symposium of the AmericanVacuum society, Oct. 1999 ²Langowski, H. C., 39^(th) Annual TechnicalConference Proceedings, SVC, pp. 398-401 (1996) ³Technical Data Sheet

As the data in Table 1 shows, the barrier stacks of the presentinvention provide oxygen and water vapor permeation rates several ordersof magnitude better than PET coated with aluminum, silicon oxide, oraluminum oxide. The barrier stacks are extremely effective in preventingoxygen and water penetration to the underlying components, substantiallyoutperforming other barrier coatings on the market.

The preferred deposition process is compatible with a wide variety ofsubstrates. Because the preferred process involves flash evaporation ofa monomer and magnetron sputtering, deposition temperatures are wellbelow 100° C., and stresses in the coating can be minimized. Multilayercoatings can be deposited at high deposition rates. No harsh gases orchemicals are used, and the process can be scaled up to large substratesand wide webs. The barrier properties of the coating can be tailored tothe application by controlling the number of layers, the materials, andthe layer design. Thus, the present invention provides a barrier stackwith the exceptional barrier properties necessary for hermetic sealingof an environmentally sensitive display device. It permits theproduction of an encapsulated environmentally sensitive display device.

While certain representative embodiments and details have been shown forpurposes of illustrating the invention, it will be apparent to thoseskilled in the art that various changes in the compositions and methodsdisclosed herein may be made without departing from the scope of theinvention, which is defined in the appended claims.

What is claimed is:
 1. An encapsulated display device comprising: asubstrate; an environmentally sensitive display device adjacent to thesubstrate, wherein the environmentally sensitive display device isselected from liquid crystal displays, and electrophoretic inks; and atleast one first barrier stack comprising at least one first barrierlayer and at least one first polymer layer, the at least one firstbarrier stack adjacent to the environmentally sensitive display device,wherein the at least one first barrier stack encapsulates theenvironmentally sensitive display device, and wherein the oxygentransmission rate through the at least one first barrier stack is lessthan 0.005 cc/m²/day at 23° C. and 0% relative humidity.
 2. Theencapsulated display device of claim 1 further comprising at least onesecond barrier stack located between the substrate and theenvironmentally sensitive display device, the at least one secondbarrier stack comprising at least one second barrier layer and at leastone second polymer layer.
 3. The encapsulated display device of claim 2wherein the at least one second barrier layer is substantiallytransparent.
 4. The encapsulated display device of claim 2 wherein theat least one second barrier layer is substantially opaque.
 5. Theencapsulated display device of claim 2 wherein at least one of the atleast one second barrier layers is selected from opaque metals, opaquepolymers, opaque ceramics, and opaque cermets.
 6. The encapsulateddisplay device of claim 2 wherein at least one of the at least onesecond polymer layers comprises an acrylate-containing polymer.
 7. Theencapsulated display device of claim 1 wherein the at least one firstbarrier layer is substantially transparent.
 8. The encapsulated displaydevice of claim 1 wherein at least one of the at least one first barrierlayers comprises a material selected from metal oxides, metal nitrides,metal carbides, metal oxynitrides, metal oxyborides, and combinationsthereof.
 9. The encapsulated display device of claim 8 wherein the metaloxides are selected from silicon oxide, aluminum oxide, titanium oxide,indium oxide, tin oxide, indium tin oxide, tantalum oxide, zirconiumoxide, niobium oxide, and combinations thereof.
 10. The encapsulateddisplay device of claim 8 wherein the metal nitrides are selected fromaluminum nitride, silicon nitride, boron nitride, and combinationsthereof.
 11. The encapsulated display device of claim 8 wherein themetal oxynitrides are selected from aluminum oxynitride, siliconoxynitride, boron oxynitride, and combinations thereof.
 12. Theencapsulated display device of claim 1 wherein the at least one firstbarrier layer is substantially opaque.
 13. The encapsulated displaydevice of claim 1 wherein at least one of the at least one first barrierlayers is selected from opaque metals, opaque polymers, opaque ceramics,and opaque cermets.
 14. The encapsulated display device of claim 1wherein the substrate comprises a flexible substrate material.
 15. Theencapsulated display device of claim 14 wherein the flexible substratematerial is selected from polymers, metals, paper, fabric, andcombinations thereof.
 16. The encapsulated display device of claim 1wherein the substrate comprises a rigid substrate material.
 17. Theencapsulated display device of claim 16 wherein the rigid substratematerial is selected from ceramics, metals, and semiconductors.
 18. Theencapsulated display device of claim 1 wherein at least one of the atleast one first polymer layers comprises an acrylate-containing polymer.19. The encapsulated display device of claim 1 further comprising atleast one functional layer adjacent to the substrate.
 20. Theencapsulated display device of claim 19 wherein the at least onefunctional layer is selected from organic layers, inorganic layers,planarizing layers, electrode layers, antireflective coatings, orscratch resistant layers.
 21. The encapsulated display device of claim 1wherein the at least one first barrier layer comprises two barrierlayers in contact with one another.
 22. The encapsulated display deviceof claim 21 wherein the two barrier layers are made of the same barriermaterial.
 23. The encapsulated display device of claim 21 wherein thetwo barrier layers are made of different barrier materials.
 24. Theencapsulated display device of claim 1 wherein the water vaportransmission rate through the at least one first barrier stack is lessthan 0.005 gm/m²/day at 38° C. and 100% relative humidity.
 25. Theencapsulated display device of claim 1 further comprising a lid adjacentto the at least one first barrier stack.
 26. The encapsulated displaydevice of claim 1 wherein the oxygen transmission rate through the atleast one first barrier stack is less than 0.005 cc/m²/day at 38° C. and90% relative humidity.
 27. An encapsulated display device comprising: atleast one first barrier stack comprising at least one first barrierlayer and at least one first polymer layer; an environmentally sensitivedisplay device adjacent to the at least one first barrier stack, whereinthe environmentally sensitive display device is selected from liquidcrystal displays, and electrophoretic inks; and at least one secondbarrier stack comprising at least one second barrier layer and at leastone second polymer layer, wherein the at least one first barrier stackand the at least one second barrier stack encapsulate theenvironmentally sensitive display device, and wherein the oxygentransmission rate through the at least one first barrier stack or the atleast one second barrier stack is less than 0.005 cc/m²/day at 23° C.and 0% relative humidity.
 28. The encapsulated display device of claim27 further comprising a substrate adjacent to the at least one firstbarrier stack on a side opposite the environmentally sensitive displaydevice.
 29. An encapsulated display device comprising: a substrate; anenvironmentally sensitive display device adjacent to the substrate,wherein the environmentally sensitive display device is selected fromliquid crystal displays, and electrophoretic inks; and at least onefirst barrier stack comprising at least one first barrier layer and atleast one first polymer layer, the at least one first barrier stackadjacent to the environmentally sensitive display device, wherein the atleast one first barrier stack encapsulates the environmentally sensitivedisplay device, and wherein the water vapor transmission rate throughthe at least one first barrier stack is less than 0.005 gm/m²/day at 38°C. and 100% relative humidity.
 30. The encapsulated display device ofclaim 29 wherein the oxygen transmission rate through the at least onefirst barrier stack is less than 0.005 cc/m²/day at 38° C. and 90%relative humidity.
 31. The encapsulated display device of claim 29wherein the water vapor transmission rate through the at least one firstbarrier stack is less than 0.005 gm/m²/day at 38° C. and 100% relativehumidity.
 32. The encapsulated display device of claim 29 furthercomprising at least one second barrier stack located between thesubstrate and the environmentally sensitive display device, the at leastone second barrier stack comprising at least one second barrier layerand at least one second polymer layer.
 33. The encapsulated displaydevice of claim 29 wherein at least one of the at least one firstbarrier layers comprises a material selected from metal oxides, metalnitrides, metal carbides, metal oxynitrides, metal oxyborides, andcombinations thereof.
 34. The encapsulated display device of claim 33wherein the metal oxides are selected from silicon oxide, aluminumoxide, titanium oxide, indium oxide, tin oxide, indium tin oxide,tantalum oxide, zirconium oxide, niobium oxide, and combinationsthereof.
 35. The encapsulated display device of claim 33 wherein themetal nitrides are selected from aluminum nitride, silicon nitride,boron nitride, and combinations thereof.
 36. The encapsulated displaydevice of claim 33 wherein the metal oxynitrides are selected fromaluminum oxynitride, silicon oxynitride, boron oxynitride, andcombinations thereof.
 37. The encapsulated display device of claim 29wherein at least one of the at least one first barrier layers isselected from opaque metals, opaque polymers, opaque ceramics, andopaque cermets.
 38. The encapsulated display device of claim 29 whereinat least one of the at least one first polymer layers comprises anacrylate-containing polymer.
 39. The encapsulated display device ofclaim 29 wherein the at least one first barrier layer comprises twobarrier layers in contact with each other.
 40. The encapsulated displaydevice of claim 39 wherein the two barrier layers are made of the samebarrier material.
 41. The encapsulated display device of claim 39wherein the two barrier layers are made of different barrier materials.42. The encapsulated display device of claim 29 further comprising atleast one functional layer adjacent to the substrate.
 43. Theencapsulated display device of claim 41 wherein the functional layer isselected from organic layers, inorganic layers, planarizing layers,electrode layers, antireflective coatings, or scratch resistant layers.44. An encapsulated display device comprising: a substrate; anenvironmentally sensitive display device adjacent to the substrate,wherein the environmentally sensitive display device is selected fromliquid crystal displays, and electrophoretic inks; and at least onefirst barrier stack comprising at least one first barrier layer and atleast one first polymer layer, the at least one first barrier stackadjacent to the environmentally sensitive display device, wherein the atleast one first barrier stack encapsulates the environmentally sensitivedisplay device, and wherein the oxygen transmission rate through the atleast one first barrier stack is less than 0.005 cc/m²/day at 38° C. and90% relative humidity.